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Color in Orion

I am new to observing. I was out tonight with my 12" Dob. Normally Orion is a colorless fan shaped cloud. Tonight after a few hours viewing I went to Orion. In the center was cobalt blue, and the edges of the fan were very pink. I had my wife look at it but she saw no color. Every time I looked the color was unmistakable. Is this my imagination? Why couldn't my wife see it? I also noticed more detail than any other viewings, and it seemed larger.

You mentioned you were out for a few hours viewing. I'm sure your eyes were very well adapted to the dark, and if the seeing conditions were good, you did see color. Was your wife out with you all night too? If she wasn't, her eyes may have not been adapted when she looked through the eyepiece.

It's not your imagination, people can and do see color in the Orion Nebula through larger telescopes from very dark sites when they are very well dark adapted. Your wife possibly wasn't as well dark adapted as you, or her vision at night isn't the same as yours. I never have seen color in M-42 other than a greenish tinge, but I have seen nebulosity spilling out of the field of view in all directions through my 10 and 15-inch. You certainly had a very clear transparent sky and no interference from either the moon or light pollution. The fact you have very good vision at night doesn't hurt either.

Blue-green should be the dominant color, as the O-III doublet and H-beta emission lines happen to fall pretty much right at the peak of sensitivity of the eye. Red is more doubtful, as the eye's sensitivity to the H-alpha line is perhaps 5-10% of that at the mid spectrum (and less when dark adapted.)

One need not be well dark adapted to see the greenish color of such a bright nebula as the inner region of M42; the surface brightness is just about as high as any nebulosity can get.

The only red I'd credit the possibility to detect would have to be in or near this brightest central region, in order that the surface brightness be high enough to activate the retina's cones. And then the red must 'compete' with the more readily seen and vusually dominant green. In the outer parts of the nebula the surface is just too low to detect the red. It's well known that in even colorless glows the visual system tends to perceive the brighter and dimmer parts as greenish and reddish, respectively. Of course, the great familiarity we have gained from innumerable color images must at least on a subconscious level lead to bias. I don't recall observations from the age of visual observtions prior to color imaging which reported unambiguous detection of reds in nebulae like we find today. And the instrument is not a factor here; the poorer system transmissions in the days of old were not sufficiently bad to make that much of a difference at all.

Through a 16" I've managed to detect a hint of red in the Huygenian region of M42. It was subtle at best, what with the preponderance of those pesky greenish photons flooding the view. But red outside that region? Not for me.

The workings of the eye are rather complicated, I offer no explanations...

After only seeing the green for the past 20 years or so, in the past year, viewing the Orion Nebula from a dark site with my 12.5 inch, 16 inch and 25 inch scopes using exit pupils of about 3mm-4mm, I often see the central region as "electric green" and the "wings" as a faint, rust red.

It might be that the red is merely result of the brain's processing the image, that the red results from it being a complimentary color to the green.

I do question the need for a fully dark adapted eye since dark adaptation does not improve one's color vision, I suspect a fully dilated eye which only takes a moment that is in the process of adapting might be best suited for seeing color. In my experience bright nebulae like NGC6572, the Blue Racketball show the most color when there is some bright light (the moon works well) around. Earlier this year while viewing for a normally dark site with a nearly full moon, NGC6572 appeared more intensely green than I had previously seen it. It remained green at high magnifications (small exit pupils) in scopes both large and small..

Interesting to see different perspectives on the color ranging from colorless to various different colors. I see the Orion Nebula as absolutely green, every time. I have never seen reds or pinks in it and I look at it anytime it's in the sky.

Be that as it may, under excellent conditions I have on a number of occasions seen blue and green shades in the area around the Trapezium and a brownish-red hue in M42's wings through large aperture Dobs from dark sites.

I could make out no color on M42 with the 10", with the 16" I see a pale green tint. Others looking thru the 16" report pink, blue and green. Last week I was trying for the G and H stars when at 385x the E and F stars took on a burnt orange color. This is the first time I have seen this. No luck with the faint G and H stars.

I am new to observing. I was out tonight with my 12" Dob. Normally Orion is a colorless fan shaped cloud. Tonight after a few hours viewing I went to Orion. In the center was cobalt blue, and the edges of the fan were very pink. I had my wife look at it but she saw no color. Every time I looked the color was unmistakable. Is this my imagination? Why couldn't my wife see it? I also noticed more detail than any other viewings, and it seemed larger.

Congratulations on such a fantastic sight!I do believe you.I have good reason to know and understand everyone's eyesight is not the same.

The Orion Nebula is one of my favorite objects .Usually it just looks gray,and very rarely a faint rose.The extent of the nebula grows the longer I am out viewing so that it is well beyond the FOV of my modest plossls even the 25mm. Several nights this fall have been very good with the nebula as large or larger than I had seen it ,yet no color ,though it looked three-dimensional more so than in previous years.Viewed this fall with scopes of 5 (Bushnell Mak)to 12 ( Z12) inches and always striking appearance.

I am thinking it may be a bit of both, mostly wishfull thinking, I have very good acuity and with a 16" scope I could see a strong shift to the green side and the faintest hint of pink but I was hoping as much as seeing..But as long as you are out there and excited is enough...Your mind can play some amazing tricks when desire is high enough...

OK...just got in. With a 90mm mak I get a white cloud and with a 12" dob I am still getting the blue center and pink outlying areas with maybe a hint of green. I am guessing it to be real. I also get pink in the flame and horsehead nebulas. I can't resolve any real details, but the dim nebulosity (did I invent that word?) is tinged with pinkness.

I never have seen pinks in IC-434. Once I was looking at it through a very large telescope with a H-beta filter, and the nebula looked reddish. Of course the Horsehead was there too, like a black horse. I only seen it this way once, from a very dark location.